To fight monsters you got to join a cata group or make one yourself. Theres two types of cata; The classic cata: Waves of monsters, 1,2,3,4 (maximum of 9 waves) etc.. These are the hard catas, the mosnters have lots of life and deal lots of damage. Maze cata: this is the easy cata where you travel through a labyrinth encountering random waves of monsters along the way, these are easy monsters they have fairly low life and deal fairly low dmg but you might be unlucky and get 9waves of them in a row. In the maze you can also encounter a "warm light" wich heals your party, an "evil presence" this will increase the monsters life and dmg drastically making it much harder to complete the wave (if you get a wave of 9 ur fucked unless you have a gosu group

), "the room spins" this will teleport you to a new location in the maze. In the maze the drops are mainly low lvls drops 1-10~ but if your lucky enough to find a chest you might find "maze only" and high lvl items. The maze cata is ideal for beginners and for soloing.
To start a fighting simply press engange.
To know more read the game mechanics styckies on the ladder slasher forum

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